Photodynamic therapy (PDT) in the multidisciplinary treatment of brain tumors: A feasibility study.

Abstract

2094 Background: Usual treatment of brain tumors includes surgery, radiotherapy and chemotherapy, but the general prognosis is bad, with local relapse as the main cause of death. PDT is a local anticancer treatment that has showed promising results in other tumors (GI, H&N, etc) and can be administered in addition to the classical modalities. Methods: Patients (pts) diagnosed of primary, relapsed or metastatic (mets) brain tumors received an endovenous photosensitizer agent (Photofrin or Foscan). After a 2-4 days period, the tumor was removed. The residual cavity was exposed to a special laser during a predetermined time, in order to achieve the optimal activation of the photosensitizer that, once activated, kills the residual tumor cells. Complementary treatment with radio and chemotherapy was also administered after surgical recovery. Results: From December 2000 to January 2011, 51 pts (34 M/ 17 F; age 13-73, median 51) were treated with a total of 61 procedures (22 Photofrin, 39 Foscan). Diagnoses were glioblastoma (20), gliosarcoma (1), anaplastic astrocitoma (9), grade 2 astrocitoma (7), oligodendroglioma (6, 2 anaplastic), malignant meningioma (1), lung ca. mets (4), breast ca. mets (3). 18/44 primary CNS tumor pts had PDT at the initial resection procedure and 32 procedures were performed at the time of relapse. In 10 cases a second procedure was performed after relapse. Toxicity: 2 pts with thalamic gliomas died in the first 24 h; 6 pts presented postoperative neurological alterations, recovering in 3 to 17 days, and 4 pts presented cutaneous ulcerations related to the PDT, one of them requiring plastic surgery. Median OS of the treated primary brain tumors was 13 m (0-120+) and 8 pts are alive at 1+, 71+, 92+, 93+, 96+, 98+, 104+, and 120+ m (1 GBM, 1 AA, 3 grade 2 A, 3 OD). Conclusions: PDT can be safely used in the multidisciplinary treatment of brain tumors. In this group of heavily treated pts, it clearly benefits some of them, showing an improvement in OS over expected from historical data. Further studies are warranted.